Fluid extracting apparatus



Oct. 10, 1961 D. B. VINCENT 3,003,412

FLUID EXTRACTING APPARATUS Filed Dec. 11, 1957 2 Sheets-Sheet l INVENTOR DANIEL 8. VINCENT BTW 14% #M ATTORNEYS Oct. 10, 1961 D. B. VINCENT 3,003,412

FLUID EXTRACTING APPARATUS Filed Dec. 11,- 1957 2 Sheets-Sheet 2 INVENTOR DANIEL B. VINCENT BYMuw hil? )(MM) ATTORNEYS United States Patent" 3,003,412 FLUID EXTRACTIN G APPARATUS Daniel B. Vincent, P.0. Box 1521, Tampa, Fla. Filed Dec. 11, 1957, Ser. No. 702,085 5 Claims. (Cl. 100-117) This invention relates to fluid extracting apparatus or dewatering presses and more particularly to such devices of the type utilizing a screw conveyor means or worzm arrangement for compressing liquid bearing materi Presses of this type are conventionally constructed with a shaft carrying the screw conveyor means and rotatably mounted in a perforated drum or cylinder having an inlet and an outlet or spill throat. It is desired for efficient operation that the screw means compress the liquid bearing material continuously as it moves through the drum. A serious problem that has confronted this art in connection with such continuous compressing is that the liquid bearing material may tend to merely rotate or churn with the screw without being compressed continuously and sufficiently to extract the desired amount of liquid. Understandably, this problem is even more serious when the press is not fully loaded, i.e., when it is not completely filled with material. Numerous attempts have been made to design the presses so that such rotation of the material will be minimized. However, for one reason or another, these attempts have not produced entirely satisfactory structures. i

A further problem is involved when it is desired that the same press be used for liquid bearing materials having difierent characteristics, such as fibrous materials and slippery materials. It is customary for commercial presses of the above type to be specifically constructed for a particular type of material and not be readily adaptable to work satisfactorily when the condition of the material to be pressed changes.

For instance, a standard fish press requires excessive motive power at reduced capacity to press fresh fish because the parts are arranged to also press spoiled or soft fish and cannot be changed without rebuilding the press. This same press cannot be used for citrus cannery waste and the like as it jams continuously and has to be completely dismantled and cleaned before it can be used again. Another type press works well on fresh fish at lower motive power but fails on soft fish because the soft mass churns within the press and will not form a pressure cake in the spill throat or outlet but channels through the entire machine in the same condition that it enters. All presses of this type fail when tried with potato starch pomace (a slick, water retentive, pectinous substance).

In the paper pulp industry many types of pulp are encountered, depending upon the process being used and the kind of wood pulp being processed. For example, newspaper stock contains short and long fiber that form separate little pellets when pressed, while kraft. pulp stock is a felt-like long fiber that compresses to a hard board-like substance when pressed. Obviously, the two require entirely difierent pressing facilities which previously have required two presses, one for each specific condition. Certain paper pulp plants find it necessary to process a particular type of wood pulp by first washing the pulp in a water bath at a concentration of only 1% of wood fibre to weight of the water being used, and then remove most of this water to produce a damp pulp substance containing 15% wood fibres. On other occasions the type of wood pulp being processed is washed in a manner in which the original concentration of wood pulp fibres to the weight of water being used is 4%, and this later is pressed to a wet pulp stock containing asaanz l aiented Oct. 10, 1961 25% solids. As can be appreciated, a plant using both types of pulp at different intervals would prefer to have a single machine that can easily be changed or adapted to handle both products.

Accordingly, for the purpose of overcoming the foregoing problems, as well as others, it is an important object of this invention to provide a novel fluid extracting apparatus, of the type referred to, involving improvements in the structure, arrangement and function of various parts.

Another object resides in the provision of a press of the type being considered and having a novel screw conveyor means arranged on the shaft and defining a plurality of axially spaced stations, each including its own flight means. A related and more specific object is to stagger such flight means in a predetermined manner and to provide novel breaker bars cooperable therewith and located between. stations whereby efiicient, superior and continuous compressing and moving of the material throughout the drum is realized, whether the press is filled or only partially filled.

It is a further object to develop a novel press of thetype referred to and adapted to operate satisfactorilywith numerous materials having difierent physical char-- acteristics, and under varying operating conditions.

A still further object is to develop a novel outlet structure in presses of the present type particularly adapted to promote optimum liquid extraction at the outlet and also smooth and continuous discharge andi to eliminate churning of the material within the press; and clogging thereof at the outlet. It is also desired; that such outlet structure be constructed and arrangedi so that it can be conveniently altered to accommodate: varying materials and conditions.

Yet another object is to provide an inexpensive, simplified and durable press construction, of the above type, capable of being conveniently assembled and disassembled.

In carrying out the foregoing objects, it is contemplated that the fluid extracting press of the invention include screw conveyor means on the shaft defined at least partially by a plurality of separate stations spaced axially along the shaft with each station including a plurality of individual and separated flights all of the same hand (i.e., all adapted to move material in the same direction). The screw conveyor means decreases in pitch going from inlet to outlet and these flights in each station are circumferentially and axially spaced from ad jacent flights in adjacent stations, each flight being of less than a full pitch, with breaker bars extending inwardly from the drum between stations. And it is further contemplated that an outwardly flared hollow mem-- ber be arranged at the outlet of the drum and that the shaft have an enlarged tapering section and also a frusto-conical element associated therewith adjacent said hollow member to define an annular discharge opening of variable size. The enlarged shaft section includes a flight of the screw conveyor means thereon, while the hollow member and frusto-conical element preferably are apertured for passage of liquid therethrough.

Further objects and advantages of the invention will be in part obvious and in part pointed out hereinafter. 5 The novel features of the invention may be best made clear from the following description and acompanying drawings in which:

FIGURE 1 is a fragmentary, side elevational view of a fluid extracting apparatus or press embodying the invention, with certain structures either cut away, shown in vertical section or omitted, all for purposes of clarity and convenience of illustration;

FIGURE 2 is a fragmentary and partially cut away side elevational view of the structure at the outlet of the press illustrated in FIGURE 1;

FIGURE 3 is a fragmentary, vertical sectional view of an a ni r a emen t r s n c h str ture shownin FIGURE 2;

tr n a f r at mb dim n FIGURE 6 is anend clevational view or" the drum and shaft of the press, with the screw conveyor omitted and,

showing a structural arrangement to be optionally substituted for the breaker bars of FIGURE 1; FIGURE 7 n S m ti n 9 m s de e ational view of a multiple press arrangement embodying the invention.

Referring now to the drawing, and particularly FIG: URES 1 and 6, numeral 26 indicates a press constructio embodying t n e t In ne a he P es inc udes a i g shaf 2 h n n mbodim n at the no e screw conveyor means of the invention thereon, to he later described in detail, and mountediorrotation within n spammed dr m or srlin 24 GUEE o a ui ble ons n d O ened eit n to de ne a mate nl n t 2% an n ma a penin 23 for flow of m l f m li ht to lef as viewed n EGURE 1. As is understood, drom 24 forms a cylinri re r h m e hin ch h qu d bear n material is compressed. i The press itseli may be mounted by any suitaole strgcwe. s y a frame h in ess Aa su able mate a in es m a s 3 may be piq e bo et 2a hi e appropriate means for collecting liquid squeezed out of the material will also be provided. The 'f eedi g moa s 31 may be in the form olf an open hoppen'or it may he in the form of a vertical pro-press to .be describedhereifiafier- A sh w n e illu trat v embs i ae i i he fe-m m n l h e a l 32 d 'qrr ite'side walls for defining such liquid collecting means, and spaced vertical walls 34, 36 38, 40 extending between the side walls 33 mount t e press. One end of shaftZZ may be iouruallecl in the wall 34 and engaged to a suitable power source, indicated generally at The shaft extends through the horizontally aligned openings in walls 36, 33 as shown, for engagement to structure at the press outlet, to be described hereinafter. Any desirable structure may be provided for assembling the apertured drum 24 in position surrounding the shaft 22.. For example as shown, longitudinally extending upper 42 and lower 44' bars or strips may be engaged to walls36, 38 by brackets 46, and the drum 24 may be longitudinally split and held in position against the strips 42, 44 bya longitudinally split framework including semi-circular elements 48 (see FIGURE 6) spaced axially along the drum and attached to strips 42, 44 m by the bolts and nuts shown. The material feeding means 31, as will be explained hereinafterin connection with an alternative embodiment of the invention, may include a mounting arrangemcntrfor an 'apertured drum 48' similar to that employed for drum 24 but arranged vertically instead of horizontally, as indicated in FIGURE 1.

Suitable structure is provided under the feeding means 31, between walls 34, 36 to collect the material delivered thereby and direct it into the press 20 through inlet 26; This structure may include a perforated trough 27; semicircular in cross section and fitted under the shaft 22 on support 59 between walls 34, 36.

In accordance with my invention, the screw conveyor means or worm means on shaft 22 and structure in the drum associated therewith, together with the structure at outlet 28- are of novel construction to achieve the objects heretofore discussed. The screw conveyor means is delined, at least partially, by a plurality of separate, axially "a cents a 4 a spaced stations within the drum, with a plurality of individual flights arranged in each station. In the illustrative embodiment, three of such stations are shown and indicated by numerals 52, 54, 56, and the flights therein are respectively designated 6%, d2, 64. It will be understood that the number of stations may be varied as desired. A first flight 58 of the screw conveyor is arranged on the shaft under 'the feeding means 31 and extends through inlet 26 to a point adjacent the first station 52, as shown.

The flights arranged in each station, as well as flight 58 are all of the same hand, i.e., will all operate to move material in the same direction through the drum to the outlet, and they are of progressively decreasing pitch in moving from station to station toward the outlet. Two of such flights are shown in each station in the illustrative embodiment; however, it should beunderstood that, if ired more n t may be arranged in a nner to that to be described for the illustrative embodiment.

A ho nr he t o fli hts n ea s on a e o xt i e 0n e s f and a e p ro m 1 ut f phas i h e ch. whe s n imp n fe t e of th in enfi the l ad n and trailing edges. of, the nigh n each s io re p ed cumteren ially and axi lly r m d: jacent loading and trailing edges of the flights in adjacent stations. When using two flights in each station, each fli t ext th u h appro m e y o eof a ta l pitch or 180 around the shaft 22, and the circumfere ial. pa b n h a j cen edges n adja s ation p ferab is npms ma y o one-fourth o he shalt circumference, as shown. lr other words, the trailins ed es 6 on the gh s 6 a e i p ed a ay m or outof phase'with the leading edges 68 on theflights 62; and the trailing edges 70 on flights 62 are similarly out of phase with the leading edges '72 on the flights 64. The trailing edge 74 qt flight 58, as shown, is disposed genera in line th a l a g 76 o ne of th flights 60. If it is desired to cmploy more than two fl g s t ach. t tio th fli ht e h sta n ll b similarly arranged and spaced. For example, it three flights are used in each station, the flights will then be approximately one-third of a full pitch, or extend around the shaft, with the edges of the flights between a t i ns b in spa e or staggered similarly to that described for the illustrative embodiment.

Each of the stations 52, 54, 55 includes breaker bars 7 8 extending inwardly from a position at the periphery or the drum 24. These bars, as shown, are arranged between adjacent stations and also at the entrance to the first station 52 and at the exit from the last station 56. I thev illustrative embodiment, two of these. bars are positioned in diametrically opposed relation between the lead n and. tr in ed s of the ht in adj s tior sand also at the endpoints of the group of stations. However, more than two of such bars could be used at each point, if desired. The bars 78 may be disposed inthcir illgstrated position in any convenient manner, fclr exampla'they may be carried by the strips 42, 4.4, as s own.

Fo e ain ypes o ate als Pa t l rly those h resist shearing such as fibrous materials, it has been found to be advantageous to incline these bars 78 away rQmthe dire tionr i n Q h t n 2 a x o pr vi de a curved contour or backward taper on the leading edge of some or; all of the flights f, as indicated in l, FIG- URE 4, whereby the material can pass between and under the flights without having to besheared; while for other materials, particularly those that are slippery and friable, ithas beenjfound to be advantageous to incline these bars in a direction toward the direction of rotation of the shaft and to have the leading edges 1 of some or all of the flights sharpened and cut. straight, as indicated in 1-, FIGURE 5. The trailing edges 2 for all of the flights, prefera ly are cut straight; as best seen in FIGURES 4 and 5.

With the afore described staggering of flights in the various stations and the arrangement of the bars 78, it has been found that a most eflicient compressing of the liquid bearing materials will occur throughout the length of the press, whether or not the machine is fully loaded with material. In particular, the coaction between the flights and the breaker bars at and between the various stations, will effectively minimize undesirable rotation of the material with the shaft so that a high degree of compression will take place in each station. In this regard, it will be noted that the staggered circumferential spacing of the flights and their progressively decreasing pitch going from station to station will offer resistance to the axial flow of material, whereby the flights in each downstream station will act as a base against which the material is forced by the preceding flights. Thus this arrangement of flights and breaker bars will bring about an axial as well as a circumferential and radial compression of the material at each station so that liquid will be continuously removed from the material throughout the length of the stations as the material moves through the press.

The invention also contemplates novel structure at the outlet 28 to cooperate with the structure Within the drum and further withdraw liquid from the material as it discharges from the machine. This structure includes a hollow and outwardly flaring member 80, an enlargement 82 on the shaft 22 including the frusto-conical section within member 80, and a frusto-conical element slidably mounted on the enlargement 82 and disposed outwardly of'the member 80. The conical element 86 is movable on enlargement 82 into or out of the hollow member 8i whereby the annular passage defined therebetween may be varied. Additionally, the element 86 preferably is also arranged to be alternately drivingly engaged to the enlargement 82 and shaft 22 whereby it will rotate therewith. Exemplary structure for accomplishing these movements will be described hereinbelow,

In the illustrative embodiment, the hollow member 89 is arranged in coaxial relation to the outlet 28 as by an axially split framework 88 (FIGURES l and 2) extending between the walls 38, 40 and suitably removably connected thereto, as by bolts (not shown) extending through the annular rings 90, 92 on the frame and the adjacent wall, as will be understood. Such a split framework arrangement can be utilized for outlet members of sizes and taper different from that of member 80, whereby such other members can be readily installed in the position of member 80, which might be desirable When di ferent conditions and/or materials are encountered by the press. This member 80 preferably is apertured. A flight means 94 of the screw conveyor preferably is formed on the frusto-conical section 84 of the shaft, such as in the manner shown.

The frusto-conical element 86 preferably is also apertured and may be arranged on the enlarged portion of the shaft by means of a spider-like frame 96 (FIGURE 3) having a collar 98 at the forward end thereof slidably and somewhat loosely embracing the shaft, with suitable means, such as screw 100 connecting the element 86 to an axial rib of the frame 96. The means for reciprocating this'element toward or away from the hollow member preferably includes a cylinder 102 and piston 104 arrangement (see FIGURE 2). As illustrated, the shaft 22 extended from element 86, through the piston and cylinder, and may be suitably journalled, as by the hearing blocks 106, 108, 110 carried by a supporting structure 112, resting on the side walls 33 of the frame for the press (see FIGURE 1).

The cylinder 102 preferably is slidable on the shaft member or enlargement 82 and piston 104, and includes suitable bearings and sealing elements 114 at either end thereof embracing the shaft 22. The cylinder may be operatively connected'to the conical element 86 as by pusher rods 116 connected to the cylinder at one end and to a pusher ring 118 at the other end (see FIGURE U 3). This pusher ring 118 may be detachably engaged to the frame 96 by any suitable means, such as bolt 120 extending through the ring and frame. As shown, a split band 122 may be suitably disposed around the ring 118 and frame 96, and connected to the ring 118 as by a set screw (not shown). The engagement of the band 122 to the frame 96 will permit relative rotation therebetween. A drainpipe 124 extends from the band 122 into a suitable liquid collecting means at the left end of the machine, as viewed in FIGURE l In the illustrative embodiment, the means for effecting reciprocatory movement of the cylinder 192 includes the fluid lines 126, 128 communicating therewith on either side of the piston 194, as shown, and extending to a source of fluid under pressure 135, such as compressed air, through suitable valves 132 for alternately pressurizing the chamber within the cylinder on one side of the piston or the other. As will be evident, when fluid pressure is introduced into the chamber in the cylinder on the right of the piston, as viewed in FIGURE 2, the cylinder will move to the right; while the introduction of fluid pressure into the opposite or left hand chamber will effect movement of the cylinder to the left. Suitable stops for limiting movement of the cylinder in either direction will be provided. It will be appreciated that arrangements for reciprocating element 86, other than the movable cylinder arrangement shown, may be sub stituted therefor and shaft 22 obviously may be divided between bearings 106, 108 if desired. The piston of the shaft can then be pinned and held stationary to bearings 108, 110.

It may be desirable in some cases, such as when thin soupy material is being handled, to have the apertured element 86 rotate with the shaft 22. For this purpose, the invention contemplates the provision of some suitable structure, such as a keyway arrangement. As indicated in the exemplary embodiment of FIGURE 3, a keyway 134 is formed on the shaft member 82 within the conical element 86, and an appropriate key 136 may be inserted through the frame 96 and into the keyway for effecting the desired connection. It will be understood that when the conical element 86 is to rotate with the shaft 22, the bolt 120 will be disengaged from the frame 96 so that the latter may rotate with respect to the band 122 and ring 118.

Operation In the operation of the press of the invention, the material will be fed from the hopper or feeding means 31 through the inlet 26 and into the drum 24 for liquid extraction at the various stations in the drum, as previously explained. The apertured element 85 will be appropriately axially positioned on the enlarged portion 82 of the shaft by operation of the cylinder 102. If fibrous materials such as paper are being processed, it has been found desirable to dispose element 86 back on the shaft somewhat, leaving a relatively wide opening between, the screen member and the element 86, and to further arrange the conical element 86 so that it will not rotate. In this position, the material will discharge in large, firmly pressed lumps. With thin, soupy material, it has been found desirable to have the conical element 86 disposed closer to the screen member 80, and to have said element rotatable with the shaft 22. In this position, the material will discharge uniformly in thin sheets.

As the material is discharged through the outlet 28, it will be further compressed by the combined action of the hollow member 89, conical element 86 and frustoconical section 84, on the shaft 22 having the flight 94 thereon. As shown, element 86, member and shaft portion 84 all taper or flare in the same direction, and the element 86 may define a flatter or more obtuse included angle than the hollow member 88 so that a converging annular discharge passageway is defined therebetween. The liquid squeezed from the material as it left of the machine, or under the cylinder 102.

the. extracted liquid will not be in a position to come in flows through this annular discharge passageway will pass through the apertured member 80 and element thereby resulthig in withdrawal of an optimum quantity of liquid in this region, inasmuch as liquid will be withdrawn from the annular discharging stream of material both in a radially outward and a radially inward direction. That is to say, liquid will pass from the discharging stream of material not only through the outer surface thereof, but also through the :innersurface thereof as the material is compressed within member 80.

The liquid passing through the apertured member 80 will flow into the region defined by the bottom wall 32, side walls 33 and walls 34, 40 of the frame. It will be noted that liquid extracted from the material within the drum 24 will also flow into this region, and a suitable drain, such as opening 138, may be provided in the bottom wall 32.

The liquid passing through the 'apertured conical ele ment 86 will flow rearwardly, or to the left in FIGURE 1, for subsequent discharge through the drainpipe 124 (FIGURE 3) into the collecting vessel defined at the Thus contact with the material discharging from the hollow member 80. Any suitable means (not shown) may be provided, for example, underneath an opening 140 formed in the base Wall 32 to collect the material discharging from the press. Although not shown, it will be understood that some appropriate removable covers or housings may be provided around the drum 2 4.and the inlets and outlets therefor.

Modifications sirable to utilize longitudinally extending bars in lieu of the generally radially extending breaker bars 78.' An illustrative arrangement of this modification is shown in FIGURE 6, wherein the drum 2.4 is provided with a suitable number of longitudinally or axially extending bars 142 spaced circumferentially therearound, as shown. It may be necessary in this arrangement, to employ shims 144 between the engaged portions of the strips 42, 44 and the screen frame, to dispose the drum 24 a greater radial distance outwardly from the shaft 22 so that the same screw conveyor means may be used. Since the material is fibrous, these bars 142 will engage the material, prevent circular movement, and satisfactory pressing will result. Another alternative arrangement, shown schematically in FIGURE 7, is particularly adapted to handle material such as paper pulp which may have a large percentage of free water, such as 96% to-99% free Water. In this arrangement, the main press 29 may beof identical construction to that described in the embodiment of FIG- URE 1; however, in place of the hopper 31 there is provided a vertically arranged preliminary or auxiliary-press 31. This vertical press, as indicated in FIGURE 7, may 7 The vertical preliminary press of FIGURE 7 difiers from the horizontal main press in that its shaft 22' does not include an enlarged end portion, and no flaring outlet member and frusto-conical element such as member 80 and element 3-6 are utilized. The drum 48 enclosing the vertical shaft 22 is also shown in FIGURE 1, suitably mounted around the shaft by a construction which may be similar to that employed for mounting the drum 24 of the main press. The press 31' may be connected to the press 20 as by the bolt and flange connection 146, with bearing 14? holding shaft 22' in position.

More than one flight 94 may be arranged on the enlargement 84 of shaft 22, as shown in FIGURE 7.

. Material is fed into the vertical press 31 through the. inlet 150 and the shaft 22' may be suitably engaged to thepower source 42 for the main shaft 22,, as by a chain during a rain.

and sprocket arrangement 152, such as that shown. Structure for imparting the desired rotation to the vertical shaft 22 from the upper pulley is indicated schematically at 154 and may be of any conventional form including, for example, beveled gears or a worm and worm wheel, as is understood. If desired, shaft 22' may be driven independently of shaft 22 by other means.

An appropriate housing 156 (see FIGURE 1) encloses the vertical press 31',and suitable means will be provided for collecting the liquid passing through the drum 43', as by providing a spillway into drain tank 33.

In addition to the advantagesalready alluded to, some further advantages of the invention might be noted at this point. In operation, each of the stations 52, 54, 56 will function somewhat as independent presses only partly dependent on the outlet structure 80, 82, 34, 86 for compression of the material within the press. In a sense, each station will function as a compression pocket with the adjacent leading and trailing edges of the flights working against the fixed compression bars 78. Also, the uniformity of the cross-sectional area of shait22, within the drum 24, causes some moisture from the material to oollect on the shaft to provide a lubricating layer in the drum which, among other things, will .further reduce the tendency of the material to rotate with or be .rotatably driven by the shaft. Such moisture will be removed together with the final pressing action at the shaft enlargement 82,84. And further, the pressure exerted on the material at the outlet by conical element 86 can be desirably controlled by the fluid pressure cushion in the active chamber of cylinder 102.

Examples of materials Some examples of the widely difierent types of material that can be satisfactorily pressed by fluid extracting apparatus of the invention will now be set forth to demonstrate, among other things, the efiiciency, versatility and adaptability of presses constructed in accordance with the invention. 7

Citrus pulp.-This is the shredded cannery waste'fiom a mixture, of orange, grapefruit, sometimes pineapple, lemon and melon waste. Itis treated with lime to partially harden the pectins and contains to moisture. it is easily pressed, but being ununiform and variable in character, the cushion conical element 86 provides for and takes up the variations in these changes and results in a final press cake of continuous flow containing 65% to 70% moisture.

Forage grasses.-These crops contain normally 70% to 95% of bound water and some free water if harvested The material is of more or less fibrous nature depending on the kind of grass being harvested, and the length of time the grass has been growing when harvested. The final press cake from this material results in a product containing.60% to 75% moisture.

Steam cook-2d firm fish-This is a somewhat firm fish meat with bones, fish oil, glue and contains an initial 75% to 80% moisture. When this material is pressed in the press of the invention, it results in a press-cake 48% to 55% moisture.

Steam cooked 50ft fish.This is a slick material, easily broken down to a soupy condition with a soft meat, bones, fish oil, and glue. The initial inbound moisture content is 75% to 80% and the final moisture content, from the press 60% to 65%.

Tomato cuZls.-Green, ripe and partly spoiled tomatoes containing 94% to 96% moisture, mostly bound in the slick tomato pulp. This material has been successfully pressed by an apparatus of the invention to a cake containing 70% to moisture, depending upon the fibrous nature of the inbound tomatoes. Usually these tomatoes have very little fibre, therefore, are difficult to press.

Potato starch p0mace.-This is the finely ground screenings from the manufacture of starch from potatoes. It is a slick foamy substance containing 90% to 96% water, mostly bound in the slick, gummy pectins that squeeze out between the fingers when one attempts to squeeze it in the hand. It cannot be successfully squeezed by hand. Only one German drum type press, and an expensive centrifugal type filter machine, have been successful in removing water from this material. Tests with the :press of the invention have been very successful in processing this waste alongside the above-named German filter and centrifugal machines. The best results obtained on the German press were 80% to 83% moisture content, and on the centrifugal machine 84% to 90% moisture content, in the press cake, while with the press of the invention it was not difiicult to reduce the press cake to 72% moisture.

Paper making pulp.Newspaper typemixture of long and short fibres mixed in and suspended in water, usually 96% to 99% free Water. It is to be reduced to any desired concentration down to 50% moisture.

Kraft type pulp.A long fibre suspended in [approximately 99% water to be reduced to any desired moisture content down to 50% water.

The present invention will thus be seen to completely and efiectively accomplish the objects enumerated hereinabove. It will be realized, however, that various changes and substitutions may be made to the specific embodiments disclosed herein for the purpose of illustrating the principles of this invention, without departing from these principles. Therefore, this invention includes all modifications encompassed within the spirit and scope of the following claims.

I claim:

1. Fluid extracting apparatus of the character described comprising: an apertured drum having an inlet and an outlet; an apertured outwardly flaring and hollow member disposed at said outlet in substantially coaxial relation to said drum; a shaft having screw conveyor means thereon being journalled in said drum coaxially therewith and extending through said outlet and said member; an apertured frusto-conical element slidably and coaxially disposed on said shaft adjacent to and externally of said hollow member, said element flaring in the same direction as said member; means for draining fluid passing through said apertured element; means providing for axial movement of said element on said shaft toward or away from said member, and means for releasably drivingly connecting said element to said shaft for rotation therewith; said shaft including an enlarged section within said member disposed between said outlet and said frusto-conical element and tapering in the said direction as said element, and said screw conveyor means including a portion disposed on said enlarged shaft section.

2. The structure defined in claim 1 wherein said means providing for axial movement of said element includes a fluid cylinder and piston disposed in coaxial relation to said shaft axially outwardly of said frusto-conical element and operatively engageable to said element.

3. Fluid extracting apparatus of the character described comprising: an apertured drum having an inlet and an outlet; an outwardly flaring and hollow member disposed at said outlet in substantially coaxial relation to said drum; a shaft having screw conveyor means thereon being journalled in said drum coaxially therewith and extending through said outlet and said member; a frusto-conical element coaxially disposed on said shaft adjacent to and externally of said hollow member; said shaft including an enlarged frusto-conical section disposed between said outlet and said element; said member, said element and said section all tapering in the same direction; the angle of taper of said element and said section being greater than the angle of taper of said member.

4. The structure defined in claim 3 wherein said element is apertured, said screw conveyor means includes a portion disposed on said enlarged section; and further wherein means are provided for draining liquid passing through said element so that such liquid will not contact material discharging from said apparatus.

5. The structure defined in claim 3 and further including means providing for axial movement of said frusto-conical element on said shaft, and means for releasably drivingly connecting said element to said shaft for rotation therewith.

References Cited in the file of this patent UNITED STATES PATENTS 647,354 Anderson Apr. 10, 1900 808,193 Bussells Dec. 26, 1905 829,314 Anderson Aug. 21, 1906 938,766 Hubert Nov. 2, 1909 1,421,282 Meakin June 27, 1922 1,851,191 Lang Mar. 29, 1932 2,149,736 Hiller et a1. Mar. 7, 1939 2,340,009 Meakin Jan. 25, 1944 2,664,814 Ahlborn Jan. 5, 1954 2,775,191 Youd Dec. 25, 1956 FOREIGN PATENTS 56,110 Germany Apr. 25, 1891 129,213 Germany July 17, 1901 500,246 Belgium Ian. 15, 1951 682,377 Germany Oct. 13, 1939 

